The purpose of this study is to determine whether Orcinoside Capsule in different doses are effective in the treatment of Depression.

And to explore the preliminary information of safety and efficacy of Orcinoside Capsule in the Chinese Patients with Depression.

Inclusion Criteria:

• Adult with primary diagnosis of major depressive disorder based on the criteria of DSM-IV-TR, single episode or recurrent episode, not accompanied with psychotic symptoms. Coding of diagnosis included:

296.21 MDD single episode, mild 296.22 MDD single episode, moderate 296.31 MDD recurrent episode, mild 296.32 MDD recurrent episode, moderate

• The subject is an outpatient.
• The subject is a man or woman,aged≥18 and ≤65 years.
• The total score of HAMD-17 is ≥18 and ≤24 in both screening visit and baseline visit.
• The subject is willing to take birth control measures during study period and one month after study.
• The subject understands and consents to takes part in this clinical trials. The subjects should sign informed consent.

Exclusion Criteria:

• The subject has a significant risk of suicide according to the investigator's opinion or has a score ≥3 on item 3(suicide assessment) of the HAMD or has made a suicide attempt.
• The subject has a current DSM-Ⅳ-TR axisⅠpsychiatric diagnosis other than depression.
• When the HAMD17 score of baseline visit compares with the screening visit, the decreasing rate is ≥25%.
• The subject has a current diagnosis or history of depression due to any other psychotic disorder or a general medical condition, bipolar disorder, or depression accompanied with psychotic symptoms.
• Any unstable cardiovascular, hepatic, renal, endocrine(thyroid gland dysfunction), blood,or other medical disease. Had a history of seizure disorder or other brain organic disorders.
• The subject has a diagnosis of alcohol or other substance abuse or dependence at least 1 years prior to the baseline visit.
• Known hypersensitivity to Common Curculigo Rhizome or other drugs.
• Women who were pregnant, breast-feeding, or planning to become pregnant during study. Men who have request to fertility within half of year.
• Clinically significant electrocardiographic(ECG) abnormalities or abnormal laboratory values(eg. Hepatic function above 1.5 times of clinical toplimit, renal function above toplimit, blood glucose above toplimit, cardiac troponin abnormal, thyroid gland examine index significantly abnormal).
• The subject uses antidepressant drug normally before 2 weeks of screening, and stops using psychotropic drug less than 7 half-life period (monoamine oxidase inhibitor more than 2 weeks, fluoxetine more than 1 month).
• The subject has accepted electroconvulsive therapy within 3months.
• The subject has accepted system psychotherapy within 3 months.
• The compliance of the subject is poor.
• The subject has participated in a drug clinical trial within 30 days before screening.
• The investigator think the subject is unsuitable to enrol in this clinical trial.